Method of rolling pipe



J. H. MATTHEWS METHOD OF ROLLING PIPE File May 51. 1923 FIE.I.

FIEIIII.

e w m 4 r I I3 11 wIIIIII/YII/IMIIIIIIIIIIIY/A W TNEGSES Parent JAMES H. MATTHEWS, OF PITTSBURGH, PENNSYLVANIA.

mnmon or nonmne PIPE.

Application filed Maya, 1923. Serial at. 642,462.

' To all whom it may concern:

Be it known that I, JAMES MAT- 'rnnws, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Imwhich improvements the following is a specification.

My invention relates to improvements in the manufacture of welded. ipe, and consists in a method whereby a istinctive surface appearance may be imposed on the pipe without any'appreciable increase in the cost ofmanufacture.

The invention is illustrated. diagrammatically in the accompanying drawings. Fig. I is a view in plan and Fig. II is a view in transverse section of a length of skelp. Fig. ITI is a View in perspectlve of the finished 1 e. p in the manufacture of steel' pipe, the metal isrolled to the form of a long narrow strip, termed skelp; the skelp is bent to tubular form, and the opposite edges so brought together are welded. The welding operation is performed in a welding machine; the bent skelp is rolled upon a ball and within the pass between grooved rolls, and, the metal being at the time heated, and

the pressure great, welding is efiected.

This is the operation of lap-welding. Buttwelding: is effected in similar manner by compression of the bent skelp in a pass between semi-circularly grooved rolls, but ordinarily without any ball or mandrel within.

some distinctive mark,a pipe which shall present a distinctive appearanceso that it may be known to be the product of one particular manufacturer and no other: an appearance,'that is to say, in the nature of a trade-mark.

It is desirable that such distinctive appearance be imposed upon the surface from one end to the other of a length of pipe, and along every longitudinal line upon that surface, to the end that even a small section cut from the full length of pipe shall still carry this distinctive appearance.

' Manifestly specialconfiguration of surface may be imposed upon the skelp., merely by rolling it beneath a roll whose surface is minutely shaped to give that configura-- tion. But since the skelp, after being so superficially configured, must in the further operations of pipe making pass-through the welding machine, it is manifest that, under the conditions of heat and pressure there obtaining, any irregularities of surface configuration such as might theretofore have been imposed on the skelp must to greater or less degree be rolled out again, and may be entirely eliminated, and the pipe ultimately dproduced be substantially smoothsurface again. At least, the welding ,operation will in its effect be so far obhterative of surface irregularities as to render.

originally im osed in relief, will still persist, and remain in the form of areas of contrasting appearance upon the surface of the finished article. ance will be quite independent of any appreciable irregularity of surface shape.

The appearance is adequate, to serve the ends in view.

My invention then is found in a method of production, and consists in the familiar pipe making operation, modified in these particulars: The skelp is rolled beneath a roll provided for example witha raised or sunken spiral welt or band, and in consequence the skelp is diversified with alternate raised and depressed diagonally-extending bands and grooves,'as shown in Figs. I and II. This skelp is bent and welded in usual manner, and in the weldin machine the superficial grooves and ban s are reduced more or less completely, but in indeterminable degree, to a common level. But in consequence of inequalities in pressure the areas which were in the skelp bands and grooves, present in the finished article diversity of appearance. The distinctive spiral pattern remains, and serves the purpose of identification. If any unevenness of surface remains, it wilLtend to make the distinctive marking more apparent and more enduring, particularly after exposure This contrast in appear-' of the pipe to corrosive influence. But,

even so, it 1s the distribution of pressure unually over the external surface of the pipe w en welding is in pro ess which gives in the finished article gversified surface condition; and this diversity in condition affords diversity of appearance, even after corrosion. I rely primarily upon surface condition, and secondarily, and in, some sense accidentally upon surface configuration. As I have indicated, wide choice of pat .ternis permissible in the practice of my inr ventlon.

-I claim as my invention: 1 The method herein described of roducing welded ipe with diversified s ace a pearance w 'ch consists in forming sk p with obli ue bands im&osed (upon one surface and nding the elp and we] .it to form a pipe with the so banded sur ace outside.

- In testimony my hand. a

JAMES H. MATTHEWS. ,Witnesses:

Wnimn Jemima, HERMAN Ammnson.

whereof I have hereunto set 

